The old saying is "never bet the house." But that's exactly what John Kerry (searchhas decided to do.

In an effort to fund his cash-strapped campaign, the Massachusetts senator has taken out a $6.4 million dollar loan against his half of this home in Boston's tony Beacon Hill (search).

A statement from campaign manager Mary Beth Cahill said Kerry's commitment to the race is "unquestioned," and that he is confident in the direction of his campaign is heading into the new year.

Cahill said Kerry is on the ballot in 31 states and has campaign operations in 33 states.

The injection of cash comes at a time when Kerry is launching a new 30-second television ad focusing on his energy proposals. That alone will cost in the neighborhood of $400,000.

Kerry is hoping to finish no lower than second place in the all-important Iowa caucus. Most polls have him in third place there. In New Hampshire, most polls show Kerry running second behind former Vermont Gov. Howard Dean (search). Like Dean, Kerry has decided to forgo public financing. That means he is not bound by state and federal spending limits.

The other half is presumably owned by his wife Terersa Heinz Kerry (search), a woman worth approximately $500 million who is prohibited by law from helping her husband repay this loan.

The 30-year adjustable loan has a starting rate of 3.125 percent. Payments in the first year alone will be $200,000. In the year 2002, Kerry's income tax returns show he made only $144,000. Campaign officials refuse to discuss Kerry's wealth, except to say he has several millions dollars at his disposal. Kerry has already lent his campaign a personal loan of $850,000.

Fox News' Brian Wilson and the Associated Press contributed to this report.